package com.lxp.tksys.controller;


import com.lxp.tksys.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

@RestController
@RequestMapping("/common")
@Slf4j
public class CommonController {    //处理图片上传和下载（回显）

    @Value("${whu.path}")   //定义根路径
    private String basePath;

    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        //file是临时文件，需要转存到指定位置，否则本次请求完成后就会删除
        //log.info(file.toString());

        //如果没有路径则生成
        File dir=new File(basePath);
        if(!dir.exists()){
            dir.mkdirs();
        }

        //原始文件名
        String originalFilename = file.getOriginalFilename();
        String substring = originalFilename.substring(originalFilename.lastIndexOf("."));
        //使用uuid重新生成防止重复
        String fileName = UUID.randomUUID().toString()+substring;

        try {
            file.transferTo(new File(basePath+fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }

        return R.success(fileName);
    }

    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        try {
            //输入流,从原文件拿名字
            FileInputStream fileInputStream = new FileInputStream(new File(basePath + name));
            //输出流
            ServletOutputStream outputStream = response.getOutputStream();
            response.setContentType("image/jpeg");

            byte[] bytes = new byte[1024];
            int len=0;
            while((len=fileInputStream.read(bytes)) !=-1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
